Monday, October 15, 2018

Waxing Crescent Moon on Sunday, October 14, 2018

The wind finally died down on Sunday evening. That let me take a picture of the moon through my telescope. The camera I used was my smart phone. I had to play with the exposure and focus settings to get an acceptable image. So below is my picture of the waxing (getting larger daily) crescent (less than half full) moon.

The nearly first quarter moon

Idaho Skies Transcript for October 19th, 20th, and 21st

RACHEL
Welcome to Idaho Skies for October 19th, 20th, and 21st. We’re your hosts, Rachel…

PAUL
…and Paul.

RACHEL
The moon leaves the company of Mars and spends this week swimming through a rather dim part of the night sky.

PAUL
In fact, stargazers will notice that the only bright star in this part of the sky is below the moon on the 19th. The star’s name is Fomalhaut. And it’s close to our solar system, at only 25 light years away. Which is close enough for the Hubble Space Telescope to see a planet orbiting it.

RACHEL
Now let’s give a little context to this observation. Fomalhaut is very young and still surrounded in the gas cloud it condensed from. The planet is a giant planet and still very bright from its formation. And it’s very distant from Fomalhaut. So it’s not very surprising that this planet can be seen with a telescope.

PAUL
Fomalhaut is the brightest star of the Piscis Austrinis. Which is the constellation of the Southern Fish. Piscis Austrinis is below the more familiar constellation of Pisces. And Pisces is faint like the Southern Fish, but has no bright stars at all. So even though Pisces is big and overhead, it’s almost never seen by the causal stargazer.

RACHEL
Fittingly, Piscis Austrinis is considered the parent of the two fish in Pisces. In constellation maps, Fomalhaut is located at the mouth of the fish. And the fish’s mouth is turned upward so it can swallow the water pouring from the jar of Aquarius.

PAUL
That’s Idaho Skies for the 19th, 20th, and 21st of October.

RACHEL
Be sure to read our blog for additional information. It’s at idahoskies.blogspot.com.

For Idaho Skies this is Rachel…

PAUL
…and Paul.

RACHEL
Dark skies and bright stars.

Idaho Skies Transcript for October 17th and 18th

PAUL
Welcome to Idaho Skies for October 17th and 18th. We’re your hosts, Paul…

RACHEL
…and Rachel.

PAUL
It’s now winter for the Northern Hemisphere of Mars.

And you can find this planet quite easily.

RACHEL
You’re guaranteed to find this planet by following the moon’s lead on the 18th. That orangish star you’ll see to the right of the moon is the Red Planet. Now Mars is a tiny planet with a diameter only half the diameter of Earth. And its small size means gravity is only 38% as strong as it is on Earth.

PAUL
The moon is only half as large as Mars. And its surface gravity is just under half as strong its is on Mars. Now both the moon and Mars are rocky world. But while the moon is gray, Mars is a light orange.

RACHEL
Which is a little unexpected, since the rocks on the moon and Mars are similar. But since Mars has an atmosphere, the iron in its surface is rusted. And that’s similar to what we find on Earth, rusty soil after a long exposure to the atmosphere. This might be an important observation to make on the exoplanets that telescopes are discovering.

PAUL
Because if the exoplanet appears to be more gray than orange, we’ll know it’s more likely a terrestrial planet with no oxygen. But watch out, just because its surface is rusty, doesn’t mean the planet can support life. Because the atmosphere of Mars is a little less than 1% as dense as Earth’s. Much of the Martian atmosphere was lost to space. And what oxygen remains is locked up in rust.

RACHEL
Astronomers discovered that Mars has lost much of its atmosphere due to solar wind. Since Mars is so small, its core cooled quickly and can no longer generate a planet-wide magnetic field. And that lack of large magnetic field has allowed the sun to blow away much of the early Martian atmosphere.

PAUL
Today the rate of lose is only ¼ of a pound of atmosphere per second. But four billion years ago, the sun’s solar wind was much stronger. And it carried away over 99% of the Martian atmosphere in a geologically short period of time. Adios Martian lifeforms.

RACHEL
That’s Idaho Skies for the 17th and 18th of October.

PAUL
Be sure to follow us on Twitter @IdahoSkies for this week’s event reminders and sky maps.

For Idaho Skies this is Paul…

RACHEL
…and Rachel.

PAUL
Dark skies and bright stars.

Idaho Skies Transcript for October 15th and 16th

RACHEL
Welcome to Idaho Skies for October 15th and 16th. We’re your hosts, Rachel…

PAUL
…and Paul.

RACHEL
Earth’s Northern hemisphere recently passed the autumnal equinox. Meaning that its fall in the northern hemisphere and spring in the southern.

PAUL
Mars, on the other hand, reaches the solstice on October 16th. But in case of Mars, it’s the winter solstice for its Northern hemisphere. Recall that the solstice and equinox occur as Earth’s spin axis, or poles tilt towards or away for the sun. So when a planet’s spin axis is tilted towards the sun, it’s summer in that hemisphere. And when it’s straight up and down, its either fall or spring.

RACHEL
Since Earth and Mars are independent worlds, their spin axes point in different directions. Earth’s spin axis points to Polaris, or the star at the end of the Little Dipper. While Mars’ spin axis points towards an area with no bright star. In fact, it’s an empty part of the sky northeast of Deneb.

PAUL
Deneb is the bright star nearly overhead these evenings. And the Martian North Pole points to a spot about the width of your fist northeast of Deneb. If you check this region out tonight, you’ll see for yourself that it’s very bare of bright stars. Meaning future Martian Boy Scouts will not have a guide star like they do on Earth.

PAUL
That’s Idaho Skies for the 15th and 16th of October.

RACHEL
Be sure to read our blog for additional information. It’s at idahoskies.blogspot.com

For Idaho Skies this is Rachel…

PAUL
…and Paul.

RACHEL
Dark skies and bright stars.

Monday, October 8, 2018

Falcon 9 Launch out of Vandenberg AFB

I hope you got to see the launch of Falcon 9 from Vandenberg AFB Saturday night. We were able to see the second stage exhaust plume as the rocket arced over the horizon form near Homedale.


On it's way up

Arcing over

Heading down to the Southern Hemisphere

Idaho Skies Transcript for October 12th, 13th, and 14th

PAUL
Welcome to Idaho Skies for October 12th, 13th, and 14th. We’re your hosts, Paul…

RACHEL
…and Rachel.

BRING DOWN MUSIC

PAUL
This weekend would be a great time to go moon watching.

RACHEL
First of all, Earthshine is becoming visible again. It’s easier to see Earthshine if you use your binoculars. So aim binoculars at the moon and look for a faint illumination over its dark portion.

PAUL
That illumination comes from sunlight, but its sunlight that reflected off Earth’s clouds. Most people think it’s the Earth’s oceans that would be the most reflective. But it’s not. The Apollo astronauts commented on just how dark the oceans and continents appears from the moon. That means, the cloudier Earth is, the brighter Earthshine becomes. And this has given climatologists another way to gauge the effects of climate change by looking at Earthshine reports from the past.

RACHEL
But it’s not just Earthshine you’ll see this weekend. Because on the 14th, Saturn appears just one degree below the moon. Saturn will be the brightest mellow star below the moon, so you can’t miss it. While binoculars can’t show you Saturn’s rings, they will show you other treats in the area.

PAUL
Surrounding the moon on its right side are several star clusters and nebulae. These are smaller and fainter than the Beehive star, so you’ll need to get out from under the street lights. But even a short distance away from town will make the sky plenty dark enough. So if you get the chance, be sure to scan the sky around the moon for small fuzzy glowing clouds. Some of them will even contain a sprinkle of stars.

RACHEL
That’s Idaho Skies for the 12th, 13th, and 14th of October.

PAUL
Be sure to follow us on Twitter @IdahoSkies for this week’s event reminders and sky maps.

For Idaho Skies this is Paul…

RACHEL
…and Rachel.

PAUL
Dark skies and bright stars.

Idaho Skies Transcript for October 10th and 11th

RACHEL
Welcome to Idaho Skies for October 10th and 11th. We’re your hosts, Rachel…

PAUL
…and Paul.

RACHEL
The three-day old makes its evening reappearance on the 11th.

PAUL
Since it’s so young, it won’t appear very far from the sun.

Which means it won’t be very high above the horizon either.

But if you look just above the southwest horizon at 8:00 PM, you should be able to the waxing crescent moon.

And you know what else you’ll be able to see?

RACHEL
Jupiter.

Our largest planet will appear just below the moon.

In fact, they’re close enough that both can be seen together in binoculars.

Jupiter may be easier to find since it’s a bright spark of light.

And not an extended crescent like the moon.

PAUL
From our perspective, Jupiter is traveling to the other side of the solar system.

But that’s really due to the fact that Earth travels once around the sun in just one year.

While Jupiter takes 12 years to do the same thing.

So in reality, it’s Earth pulling ahead of Jupiter and that makes it look like its traveling to the other side of the sun.

RACHEL
By the end of October, or perhaps the beginning of November, Jupiter will be too close to the sun to be seen.

Therefore, take some time out during the next two weeks to see Jupiter in the evening for the last time this year.

Jupiter will become a morning planet in the east sometime after early December.

And then an evening planet in May next year. 

PAUL
That’s Idaho Skies for the 10th and 11th of October.

RACHEL
Be sure to read our blog for additional information. It’s at idahoskies.blogspot.com.

For Idaho Skies this is Rachel…

PAUL
…and Paul.

RACHEL
Dark skies and bright stars.

Idaho Skies Transcript for October 8th and 9th

PAUL
Welcome to Idaho Skies for October 8th and 9th. We’re your hosts, Paul…

RACHEL
…and Rachel.

PAUL
Comet Giacobini-Zinner is passing through the inner solar system this month.

Which means its appearing at its brightest.

Unfortunately, this comet is not very bright to begin with.

However, as it rounds the sun, its surface is warming up and some of its ices are sublimating.

RACHEL
Sublimating is when a solid changes directly into a gas.

As comets sublimate, the escaping gases carry away cometary dust.

Which remains within the comets orbit.

And can eventually, cross the orbit of our home world.

PAUL
As it does, the dust slams into the atmosphere at speeds greater than 25,000 miles per hour.

High speeds like this violently compress the air ahead to make it very hot.

In fact, hot enough to melt the dust into what we call a meteor.

RACHEL
Just by chance, meteors from Comet Giacobini-Zinner reach their peak intensity on night of the 9th.

They’ll appear to radiate from a point in the sky that also contains the head of Draco the Dragon.

So this meteor shower is called the Draconids.

Usually, there aren’t very many Draconids hour, but the shower has been known to surprise stargazers.

PAUL
So if you have time on the night of the 9th, look in the high northwest for the head of Draco the Dragon.

Which is to the right of the bright star Vega.

Any Draconid meteors will appear to originate from the squashed square of Draco’s head.

And with the moon at new, its light won’t interfere with seeing this meteor shower. 

RACHEL
That’s Idaho Skies for the 8th and 9th of October.

PAUL
Be sure to follow us on Twitter @IdahoSkies for this week’s event reminders and sky maps.

For Idaho Skies this is Paul…

RACHEL
…and Rachel.

PAUL
Dark skies and bright stars.

Monday, October 1, 2018

Idaho Skies Transcript for October 5th, 6th, and 7th

RACHEL
Welcome to Idaho Skies for October 5th, 6th, and 7th. We’re your hosts, Rachel…

PAUL
…and Paul.

RACHEL
Early rising Idaho stargazers will find the moon near the brightest star of Leo the Lion on the 5th. The star is yellowish-orange in color and its named Regulus. The star’s color and position within the constellation makes it the heart of this celestial lion. But it’s a heart that’s three times larger than the sun, or 2.7 million miles across.

PAUL
Did you know that Regulus is a fast rotator? In fact, it spins on its axis in only 16 hours. Or 45 times faster than the sun. If Regulus rotated three hours more quickly, the star’s gravity would be insufficient to hold it together. And the star would tear itself apart.

RACHEL
Astronomers have determined that Regulus is young, only 50 million years old. While that might not sound young to you and me, in star years, that’s very young. And Regulus won’t live nearly as long as the sun. That’s because Regulus is massive, over three times heavier than the sun. Which makes its core hotter and denser.

PAUL
Astronomers know that it’s the heat and pressure that drives stellar fusion. Higher heat and pressure makes the rate of fusion in Regulus is much higher than in the sun. So it’s not surprising that Regulus is expected to only live to be 350 million years old. Compare that our sun, which is over ten times older.

RACHEL
And our sun is only half way through its life.

PAUL
That’s Idaho Skies for the 5th, 6th, and 7th of October.

RACHEL
Be sure to read our blog for additional information. It’s at idahoskies.blogspot.com.

For Idaho Skies this is Rachel…

PAUL
…and Paul.

RACHEL
Dark skies and bright stars.

Idaho Skies Transcript for October 3rd and 4th

PAUL
Welcome to Idaho Skies for October 3rd and 4th. We’re your hosts, Paul…

RACHEL
…and Rachel.

PAUL
The Beehive star cluster is one of the most attractive star clusters. It’s a galactic star cluster, or one without a central concentration or spherical outline. And the stars in a galactic star clusters are born at the same time from the same cloud of dust and gas. But they’re relative young star clusters compared to the globular star clusters.

RACHEL
While globular star clusters can date for the beginning of the universe, or 12 billion years ago, galactic star clusters are only tens to hundreds of millions of years old. But galactic star clusters don’t die young because their stars die that soon. They only last for millions of years because by then, their stars will have drifted apart. And astronomers believe the sun was probably born in such a star cluster 4.55 billion years ago.

PAUL
To see the Beehive on the 4th, first look at the moon at about 4:00 AM. Then aim your binoculars at the waning crescent moon and you’ll see the Beehive third lunar diameters away. Specifically, to the moon’s upper left. The star cluster will appear roughly three times larger than the moon. And you’ll be able to detect more stars if you place the moon outside your field of view.

RACHEL
The Beehive is one of the closest star clusters to the solar system. Astronomers believe its distance is around 570 light years. Did you know that they have discovered at least six solar systems in the Beehive? The problem is that the Beehive is 1/7th the age of the solar system. So there’s almost no chance those planets have anything more than single cell life.
 
PAUL
That’s Idaho Skies for the 3rd and 4th of October.

RACHEL
Be sure to follow us on Twitter @IdahoSkies for this week’s event reminders and sky maps.

For Idaho Skies this is Rachel…

PAUL
…and Paul.

RACHEL
Dark skies and bright stars.

Idaho Skies Transcript for October 1st and 2nd

RACHEL
Welcome to Idaho Skies for October 1st and 2nd. We’re your hosts, Rachel…

PAUL
…and Paul.

RACHEL
Happy birthday NASA!

PAUL
President Eisenhower created the National Aeronautics and Space Administration on July 29th, 1958. And it became operation 60 years ago on the 1st. Did you know that Eisenhower created NASA to be our nation’s civilian agency to lead its peaceful use of space?

RACHEL
However, he grudgingly created it in response to the Soviet launch of Sputnik 1. Grudgingly because the launch of Sputnik 1 lead many Americans to think that the US was backwards in space technology. When he understood that we were not.

PAUL
Meanwhile, a different organization, the Advanced Research Projects Agency, or ARPA, was created to manage the development of our nation’s military space technology. So things like spy satellites fell under the prevue of ARPA. Now before NASA, there was an organization called the National Advisory Committee for Aeronautics, or NACA. And it was responsible for leading our nation in aeronautical research. But it was dissolved on October 1st, 1958 and all its facilities were turned over the NASA.

RACHEL
One of NASA’s first tasks was putting an American into space and returning him safely. Later, President Kennedy tasked it with putting a man on the moon and returning him safely to Earth. Meanwhile, NASA was also seeing to the launch of unmanned spacecraft that have explored the solar system. And today it is responsible for space telescopes that have located massive black holes and exoplanets.

PAUL
One of its challenges today is to incorporate commercial spaceflight into its explorations. With companies like Elon Musk’s SpaceX.

RACHEL
That’s Idaho Skies for the 1st and 2nd of October.

PAUL
Be sure to read our blog for additional information. It’s at idahoskies.blogspot.com

For Idaho Skies this is Paul…

RACHEL
…and Rachel.

PAUL
Dark skies and bright stars.